1. Field of the Invention
The present invention relates to ceiling fans and, more particularly, relates to ceiling fans with light fixtures including a light-sensitive night light feature.
2. Description of the Prior Art
It is well known that ceiling fans which include lighting units play an important role, particularly in residential settings, in providing comfort, safety and security for both persons and personal property within a particular residence. For instance, a homeowner or resident may leave his home during the daylight hours and not return until after dark. Unless the person leaves a light on before leaving his residence, a practice which wastes electricity and, therefore, money, that person will return home to a dark and potentially dangerous dwelling. Not only may the returning homeowner damage his personal property while attempting to locate and turn on a light switch but, in addition, the homeowner may fall and injure himself in the process. Even more foreboding is the possibility that an intruder may be waiting in the darkness to attack the unsuspecting homeowner. It is also to be noted that it would be advantageous to leave a ceiling fan on during these times to provide continuous air circulation, and thus increased efficiency in heating and cooling the home.
Another situation which poses a more direct hazard to a homeowner's personal property occurs when the homeowner goes away on vacation for several days. It is commonly known that burglars will watch a target residence for several days prior to actually burglarizing the home. It quickly becomes obvious to the burglar that the homeowner is away when no lights are on in the residence over the course of consecutive nights. Leaving the ceiling fan on during such extended periods away from the home is equally advantageous in heating and cooling the home, in addition to reducing the effects of stagnant air during a time when windows and doors are likely closed.
Attempts to combat such potentially hazardous low-light situations have included the use of mechanical timers to control the turning on and off of light fixtures within the residence. However, mechanical timers suffer from many disadvantages. For instance, homeowners who are not mechanically inclined find the actual setting of the timers to present insurmountable difficulty. The person fortunate enough to be able to set the timers properly is then left with the possibility that the timers, many of which are poorly designed or constructed, will not perform their operation properly. Also, it can be understood that the sight of a rather large timer protruding from a power outlet or ceiling fan may not be aesthetically pleasing to the homeowner. Further, the installation of timers in pre-existing ceiling fans poses the problem of finding a location to mount the timer in an easily accessible location.
However, even if the mechanical timers function properly, another disadvantage associated with their use is that they only have the potential to completely turn on or completely turn off the light fixtures which they are controlling. In other words, an illumination level of the light fixture is not adjustable to levels between a fully-on or a fully-off level, such as a night light. This is a disadvantage in that lighting conditions may warrant the need to have at least some intermediate level of light present during daylight hours. For instance, extremely stormy weather may present nighttime or dusk-like lighting conditions during the middle of the day. Therefore, a homeowner with a mechanical timer set for six o'clock in the evening who is returning home in the middle of the day would be faced with the same potential hazards discussed above.
In addition, even if a low level of illumination between the fully-off and fully-on levels is attainable, the light, particularly if it is incandescent, will generally flicker within a flicker range of illumination below a minimum threshold. This flicker is caused by an insufficient amount of current applied to a filament within the light to create substantially continuous illumination. Thus, flicker may result from an inadvertently low setting by the homeowner, or variations in line voltage, such as "brown-outs".
Nonetheless, despite the waste of electricity associated with leaving a light on or using the potentially unreliable mechanical timers, such solutions to the problem suffer from at least one fundamental drawback, that is, they require continuous human intervention. The homeowner must remember to turn on the light before leaving during the day, and if he makes use of timers, the homeowner must remember to reset the timers when lighting conditions change with the seasons or when the homeowner's own schedule changes. In order to avoid flicker, the homeowner must set the illumination level of the light at some point that will compensate for any potential fluctuations in line voltage, which can be difficult if not impossible for the homeowner to determine.